Question

An object is placed at a distance of 10 cm in front of a concave mirror. Its image is formed at a distance at 15 cm on the same side. The focal length of the mirror is?

• A. -6 cm
• B. 6 cm
• C. -30 cm
• D. 30 cm

Answer 1

Answer:

A. -6 cm

• Substituting the given values,

• we get 1/f = 1/(-15) + 1/(-10), which gives f = -6 cm.

• Therefore, the correct answer is, which states that the focal length of the mirror is -6 cm